Tread-surface for pavements and the like.



G. B. J AGUBS. TREAD SURFACE FOB PAVEMENTS AND THE LIKE.

APPLIOATION FILED OCT. 1,1909.

Patented Apr. 12,1910.

K iAn Leooeo UNITED fiTATES PATENT OFFICE.

ctIAn ns BfJAcoBs, or PORT CHESTER, NEW YORK, ASSIGNOR TO MURRAY AND .mcons MANUIACTUR-ING conrany. or NEW YORK, N. Y;, A conromvrxon or NEW YORK.

Specification of Letters Patent.

Application filed October 1. 1909. Serial No. 520,503,

"which people tread shall have and be capable of retaining anti-slipping properties. In other words, any such surface, while being smooth enough to afford comfortable foot way, should nevertheless be of such a nature that the footwear of pedestrians will adhere thereto and at the same time such surface fShOtIld' e capable of resisting wear or abrasion without loslng its adhering or .ant1

slipping properties.

I The invention has for its object to pro ide a tread surface which shall possess th'esequalities in a high degree. These andother objects of the invention will in part beobvious and in part'be more fully explained in-thc following description;

' In accordance with one feature of the illention, the tread surface com-prises av cast metal base with a surface layer of granular hard mineral elements, said elements being embedded in the metal of the base and of such material and size that they will not artiall 1 embed themselyes in the contact- P 3 3 inglsurfaces of footwear and thus prevent slipping. o

The "particular materials employed may be varied to suit varying conditions and purposes without'departing from the in vention, as viewed in its broader aspects. For

" most purposes has been found that a base of cast iron provided with a surface layer of granular artificial 'cormidum, known as "alundumf gives satisfactory results.

' However, other cast metals, such as brass,

or bronze, or aluminum alloys, may he used for the base, and natural corundum, carborunduni, or similar natural or artificial material, which ma be granulated and which, when granulate will not be destroyed or seriously injured by the heat of the molten metal, may be employed for the surface layer.

A tread surface of the character specified may be produced in accordance with a method which forms the subject of a copending application. This method is as follows: A mold for the tread is formed,

Patented Apr. 12, 1910. r

preferably in green sand. A surface of the mold which is to shape a resisting antislipping. surface of the tread is provided with a layer of the granular hard mineral elements, this layer preferably being caused to adheresufliciently to themold surface by lightly tamping the layer into the surface. This maybe done'by-replacing the pattern in the mold after the layer of granular material has been applied and then exerting a suitable pressure on the pattern as by tapping the pattern with the hand or amallet' so as to force the granular elements partially into the sand surface of the mold. The pattern then "removed, the mold closed, and the molten metal introduced into the mold, the metal beinglin such condition that it will penetrate the layer of granular material without destroying the elements thereof and of such a character that it will thereafter become sufiiciently rigid to effectively resist displacement of the mineral elements. The layer of granular elements should cover the surface of the mold or be so closely arranged'that, when the interstices between the elements are filled bythc cast metal, the latter will be protecte by the hard element's-from Wear or abrasio Preferably, the layer of granular elelnelnts is made to practically cover"the mold surface.

and may be given a substantial thickness, the thickness of the layer being preferably as great as the distance to which the molten metal will penetrate. The coarser the grains of the layer. the thicker it may be. Qrdi- .narily, the layer may be made-t0 adhere sutticlentlyby the application of pressure,

as above stated. Whii necessary, however,

athelayer of granular elements may be held in place on the mold surface by covering the same with some material the identity of,

whichwill be'destr'oyed by the molten metal introduced into the mold. For example, the

layer of 'ranular elements ma be held in 1. D l

place by a piece ol. thin sheet metal, hue wire gauze, or the like, which will melt or become iiurorpcu'atcd in thebody ot' the light pavement, the construction shown embodylng certain novel ieatures other than those above mentioned \YltlLl] term parts ot the invention. I

)f the drawings, Figure l is a plan view of a vault light pavement. embodying the various features of the. invention; Fig. 3. is a vertical sect-iouot' the same taken on the line 2-2 of Fig. l; and Fig. 3 is a vertical sectional view illustrating a detail on a larger scale.

While the entlre tread surface of a pavement 'or other footway may be constructed in accordance with the principal feature of the invention, in the embodiment illustrated the surface of the pavement 1s a composite surface, part being t'orined in accordance 'as concrete and glass.

' meat.

with my invention and part being formed of the materials ordinarily employed, such embodying the invention are in the form of small circular bodies or buttons '1 embedded in and perfectly uniformly distributed throughout. the body 2 of the pavedetai lin Fig. 3. .ksdtere shown, the button comprises a. body portion 1 of cast metal the surface. of which is studded with "l'illlll'.

l'ar hard mineral elements fori-niug a highly resistant, antislipping layer 3. these but.- tons being preferably constructed iii-accordance with the method above described. For the ordinary 1mveu1eut. as shown, the base of the tread surfaces i preferably formed of cast iron and the surl ace layer of granulated alundlun, as above eyplalned. In the embodiment. illustrated thebuttons are represent'edas having their resisting anti-slipping surfaces located slightly above the sur rounding surtaces ol the pavement. By

reason of this arrmigement}the highly resistant. stnzl'aecs' ol the buttons will protect the sort-molding surfaces of the pavement.

from wear and at the 'sanietime ell'ectnally" prevent slipping.

,'*While the sn'rt'a're ot the. buttons are exlre 'ncly durable. they \\lll nevertheless eventually be worn down where the pave- .-'\5 shown, the parts ()ne of the buttons is illustrated in ment much used. In accordance with one feature oi the invent ion, therefore, provision is made for readily exchanging the worn buttons for new ones. As shown, the bodyportions 1 of the buttons are externally tapered t'rom thetop downwardly and seated in correspomling taperingrecesses in the body 2 of the pavement. Where the pavement is made of concrete, as illustrated, the buttons may be intrmluccd into the concrete when the paycnu-nt is ltu'med. For the purpose of removably and yet tirmlysecuring the buttons in position they art? provided with perforations, preferably rentrally l'0- catcd, where the buttons are round, as illustrated, these perforations being adapted to receive screws 4. lreil erably and as shown, the upper ends of the perforations are countersunk to receive the heads of the screws below the level of the resistant layer 3, the said heads being thus protected from wear by said resistant layer. he threadedpoints or ends of the screws may enter any suitable anchoring device 5. \Vhile this anchoring device may be of any suitable material, such as Wood, it is preferably formed of metal and is tapped to receive the thread of the The anchoring device 1norc0'\'cr,'-is pret'e 'ably formed to extend beyond the lower edge of the button so as to be firmly embedded in the body of the concrete, being introduced with the button when the concrete is laid.

A. further future of the improvement consists in forming the perforation in the but ton with an enlarged lower portion so as to provide aninternal shoulder t) which may be engaged by a suitable implement to forcibl y detach the button from the concrete, when the button has become worn. J

1t is obvious that the resistant tread surfaces may or may not be used in connection with other surfaces to form: the pavement or footway, and that. where the Y are used in connection with other surfaces, the latter may be of any desired material. .lt isalso obvious that where: the resistant surfaces are used in connect ion with concrete, the latter may be constructed ofthe usual materials and may be in any usual or improved form. W here the conerete tornis a'vau t light pave- -ment as llustrated, it may be relnforced 1n any of the usual or approved ways and may be provided with any of the usual or approved t'orms'of vault glasses or lenses. As shown, the concrete is reinforced by rods or bars-T between whit-hare located the glasses or lenses 8. In this case the resistant buttons 1 are preferably distributed between the lenses and in the upper part of the concrete body 2 above the reinforcing bars 7, suhstam tiall as illustrated. By reason of this con struction the resistant. surfaces serve to protect the lenses and the adjacent concrete from wear and also prevent slipping uponthesmooth surfaces of the glass and the concrete.

I claim:

1. A tread comprising a base of cast metal and alayer of granular hard mineral elements embedded in the upper surface of said base, said elements being of such material and size that they will not be injuredby the heat of the molten metal when casting the base and part at least of said elements being partly exposed to prevent slipping and to protect the metal in which they are embedded from abrasion.

2. A tread comprising a base of cast iron and a-layer of granular oorundum embedded in the surface. of the base, part at least of the grains of corundum being partlyexa posed to prevent slipping and to rotect the iron in which they are embedded om abras1on.

3.9K pavement comprising a body portion of suitable paving material in combmatlon with tread. members distributed throughout the surface thereof, said tread members com-- prising each a base of cast metal and a layer of granular hard mineral elements embedded in the upper surface of the base, said elements being of such material and size that they will not be injured by the heat of the molten metal when casting the base and part at least of said elements being partly exposed to prevent slipping and to protect the metal of the base from abrasion.

4. A pavement comprising a body portion of concrete in combination with tread members consisting each of a base of cast iron and a layer'of granular corundum embedded inthe surface of the base, part at least of the particles of corundum being partly exposed to prevent slipping and to protect the iron of the base from abrasion.

5. A pavement comprising a body portion of concrete in combination with tread members consistingeach of a base of cast metal removablvv secured in the body of the concrete, an elements embedded in the surface of the base, the part at least of said elements being partly exposed to prevent slipping and to protect the'mctal of the base from abrasion.

6. A pavement comprising a body portion of concrete having tapering recesses therein in combination with tread members tapering to fit said recesses and provided with means for removably securing the same therein, said tread members having base portions and resistant surfaces formed of granular hard mineral elements embedded in said base portions.

7. A pavement comprising a body portion of concrete having recesses formed therein and anchor members embedded in the concrete below said recesses, in combination with tread members formed tofit said recesses and having base portions and resistant a layer of granular hard mineralsurfaces consisting of layers of hard mineral elements embedded in the base portions, and.

means adapted to engage said anchor members for securing said tread members in said recesses.

' 8. A pavement comprising a. body portion of concrete having recesses formed therein and threaded anchor members embedded in the concrete below said recesses, in combination with tread members formed to fit said recesses and having base portions and re sistant surfaces. consisting of layers of hard mineral elements embedded in the base portions, and screws adapted to enga e the threaded anchors and secure said trea .members in said recesses.

9. A pavement comprising a body portion of concrete having recesses formed therein and anchor members embedded in the concrete below said recemes, in combination with tread members formed to fit said recesses and having base portions and resistant surfacesconsisting of layers of hard mineral elements embedded in the base portions, said tread members being perforated and having countersunk upper portions and enlarged lower portions adapted to form shoulders to.

facilitate the removal of the tread members, and means adapted to engage said anchor members for securing said tread members in said recesses.

10. As an element of a avement, an ex: ternally tapered tread mem er comprising a perforated base portion in combination w1th an anchor, the sides .ofsaid anchor bein projected beyond the lower portion of sai base portion, and detachable means for securing the tread member to the ancllor, the wholebeing'adapted tobe embedded in concrete so that the tread member may be removed. 7 s i 11. As an element of a pavement, a re movable tread-member comprising a. perforated base portion having downwardly tapered sides adapted to be embedded in concrete and means coiiperating with said perforation for securing said tread to the concrete, the lower part ofsaid erforation bein moving the tread-member. a

12. As. an element of a p' ement, arremovable tread-member comprising a perfoenlarged to form a shouher for refrated base portion havin downwardly tapered sides, the upper on of the perforation being countersunk, in combination.

of the base, in combination with an anchor and detachable means eoacting with the perforation of said base f r seem-jug the tread uuuubrr to the author. the whole being adapted to be embedded in eoneret-e so that the tread member may be removed.

ll. As an element of a pavement, a tread member comprising a 1. ert'orated *basei'rf east iron having a layer of granular roru-ndulu embedded in its surface, in combination with an anehor and serew for securing the tread member to theaneher. the whole being adapted to be embedded in eonerete so that the tread member may be removed.

15. As anelement of a pavement, a tread member reiuprising a perforated base of cast 'iron in the surface of which is embeddetha layer of granular corundum, the upper part of the said perforation being countersunk and the lower part of said pertoration being enlarged to form a shoulder for removing the tread member, and means adapted ,to engage the countersunk portion of said perforation i 01 seeuring said treadnleinber in place. 2

in the presence of 

